CLEVELAND, Ohio - Most musicians go to specialized shops for instruments. The six members of Mantra Percussion? They go the hardware store.

They, you see, are champions of Michael Gordon's "Timber." They don't need drums, xylophones, or triangles. All they need for their upcoming appearance at the Transformer Station are six decent two-by-fours, of Douglas Fir. While shopping once, they even taped a performance at Lowe's.

"We prefer the imperfections," said Al Cerulo, the group's director, referring to the wooden planks. "What they offer harmonically is so varied.

"Percussionists are always being hit with stuff like this. In our world, we're pretty used to composers making unusual requests and not blinking an eye."

If anyone's going to blink an eye, it'll be the audience at Friday's presentation by the Cleveland Museum of Art.

Not only is the sight of six guys drumming on lumber certain to be strange. The sound they make is also guaranteed to enchant, to lull the mind into a state verging on hypnosis.

Over the course of the evening-length work, the 12 hands of the musicians will fall in and out of alignment while proceeding in different directions at different speeds. Speakers and sub-woofers will amplify the effect, enveloping listeners in a complex, kaleidoscopic web of sound.

Mastering and memorizing the work was an "unbelievably difficult" process that took almost two years, Cerulo said.

"It's such a whirlwind of a piece," he said. "There's a zone you need to get into. You don't even realize where you are until it's over. You don't realize that you've been taken on a journey."

Mantra didn't come together for "Timber," and it's not the only work in their repertoire, but it's why they're together now. Already the group has recorded the work and performed it live around the world some 100 times.

It's not like a war-horse, either. Whereas, in a mainstream concerto, a soloist can fall into a kind of routine, in "Timber," there's no chance for boredom, since every performance is unique, varying with the nature of the wood, the acoustics of the space, and any number of chance happenings.

"The experience of this piece live is hard to duplicate," Cerulo said. "We always find something new, a new way to hear or see something, and the room itself becomes one of the musicians."

That's not literally true, of course. Not even a room as sonically vibrant as the Transformer Station ranks as a member of a group united by history, friendship, and love for contemporary music.

In that way, Mantra is less of an ensemble than a band, one that plays wooden boards and performs at hardware stores. Like groups in other genres, Mantra started out playing covers, but soon shifted to bringing new music and ideas into the world.

"I wouldn't say we're trying to make a statement," Cerulo said. "We're just the medium, finding composers we enjoy and commissioning them. We're like a rock band. We just happen to play classical music."